Switching ground to reset Voltcraft DCM220W display

After reading quite a lot on the internet and watching many videos on youtube, I just bought my first Arduino Uno yesterday for a remote control project in a miniature gauge locomotive. Since (almost) everything has already been made somewhere in the world, finding examples is not to difficult and the programming turned out to be not to difficult as well.

However, I have been working on another electronics project in which no Arduino was involved, but after yesterdays experience I thought of implementing one in it as well. And that was the point where internet couldn't solve my questions for the time being.

The idea was the following:
Making an electronic counter module with a sensor, or for the ease of trying things, with a push button.
The button doesn't seem to be the problem, so does the counter module.

I have a Voltcraft DCM220W counter which works perfectly fine in a 'non-digital' system. Connecting the Arduino's 3.3V to the + and the GND to - does power the display.
The problem however, and I didn't try any code for this in order not to blow up the Arduino, is how to connect/program pins 1 and 3.
The idea is that the display counts 1 everytime pin 1 is shorted with the ground. The same idea for pin 3, which will reset the display to read 0's.

So: How can I program the Arduino in such a way that it will ONLY ground pin 1 (or 3) if it is told to do so, e.g. pushing a button or so, and won't blow up anything or do other weird things else?
Possibly without any other component, since I don't live in the electronics shop :cold_sweat:

I hope you can help me :grin: :sunglasses:

You can use digitalWrite to output a HIGH(5v) or LOW(Gnd) as needed. you will need to use a voltage divider to limit the HIGH voltage from the Uno to 3.3v this is called level shifting

However the counter is not really necessary as the Arduino can do the counting for you.

     counter = counter +1;